Board to continue Lake Ontario water level plans

by jmaloni

Fri, Nov 2nd 2012 10:50 pm

While
water level conditions in Lake Ontario have changed as a result of
heavy rains this past week from Hurricane Sandy, government overseers
of water levels in the lake and St. Lawrence River system have
elected to stick with their earlier plans.

The
International St. Lawrence River Board of Control recently reviewed
conditions in the Lake Ontario-St. Lawrence River system and decided
to continue to moderately over-discharge relative to plan-specified
flows when necessary to maintain adequate minimum water levels in the
Montreal area. When conditions downstream permit, the board will
reduce outflow to restore water back to Lake Ontario, relative to
Plan 1958-D, as soon as possible.

The
level on Lake Ontario as of Oct. 17 was 74.32 meters (243.83 feet),
still 17 centimeters (6.7 inches) above the lower regulatory limit
but 30 centimeters (11.8 inches) below the long-term average for this
time of year. Currently, the level of the lake is about 5.7
centimeters (2.2 inches) lower than it would have been had the plan
been strictly followed this year. Levels on Lake Ontario are the
lowest for this time of the year since 1964. Levels on Lake St.
Lawrence are at 73.11 meters (239.86 feet), 2 centimeters (0.8
inches) above average for this time of the year.

The
level at the Port of Montreal on Oct. 17 was 5.48 meters (17.98
feet), 80 centimeters (31.5 inches) below average. The average
September level in Montreal was a new record low, in large part
because outflows from the Ottawa River have also been at record low
values, due to the persistent drought conditions in the region.

The
board, in conjunction with its staff, continues to monitor the
drought situation carefully and is prepared to take further action as
required, while also understanding that the drought conditions may
persist into next summer, severely restricting what the board may be
able to do. The board will continue to review conditions and revise
the outflow strategy, as necessary. Outflow changes are posted to the
board's Website athttp://ijc.org/conseil_board/islrbc/en/data_informations.htm and the
board's Facebook site at http://www.facebook.com/ISLRBC.

Water
levels on both Lake Ontario and the St. Lawrence River vary
considerably from year to year depending on the weather conditions.
The board urges lake residents and boating interests to be prepared
to live within the full range of levels that have occurred. Although
the board strives to maintain the range of monthly mean levels of
Lake Ontario below the upper limit of 75.37 meters (247.3 feet) and
above the lower limit (from April through November) of 74.15 meters
(243.3 feet) specified in the orders of approval, since regulation
began in 1960, actual monthly levels have ranged from a high of 75.74
meters (248.5 feet) to a low of 73.82 meters (242.2 feet) due to
climate conditions outside the plan's design range.

Levels
on the St. Lawrence River fluctuate more widely. Furthermore,
excessive wind setup and wave action may significantly increase local
levels on both the lake and river. Strong winds can raise water
levels temporarily by over half a meter (2 feet) in some locations
with waves adding more water depth. Together, the temporary water
level increase can exceed the monthly mean upper limit and cause
shoreline damages.

The
International St. Lawrence River Board of Control was established by
the International Joint Commission in its 1952 order of approval. The
board's main duty is to ensure that outflows from Lake Ontario meet
the requirements of the IJC order; it also develops regulation plans
and conducts special studies requested by the IJC.